Ball-grinding machine.



E, HANUS.

BALL GRINDING MACHINE.

APPLICATION FILED MAY22,1914.

Lpln Patented Jan.5,1915.

FICE.v

BALLGRIN DING 'MACHINE Specification of Letters Patent.

Patented Jan. 5, 1915.

Application filed May 22, 1914. Serial N0. 840,250.

To all whom t may concern: o

.Be it known that I', EWALD HANUS, engi neer, subject of the King of Prussia, residing at N o. 14 Treskowstrasse, Tegel, near Berlin, Germany, have invented certain new and useful Improvements in or Relating to Ball-Grinding Machines, of which the following is aspecification.

The invention relates to a ball grinding machine in Which between two plates formed with annular grooves, a third plate is provided formed with grooves on both sides. In theknown machines of this kind, the central plate rotates, the two outer stationary plates being formed with a radial recess constituting a charging hopper into which the balls drop from the grooves after each revolution, are mixed therein and return in another order through other grooves of the grinding plates. According to the invention, the outer plates rotate and the central stationary plate is formed with a radial recess extending entirely through it. Thus a common charging hopper is provided for all balls whereby the construction of the machine is greatly simplified, and in addition to the usual mixing of the balls, a continuous exchange of the balls ground` on both sides of the machine is obtained. By forming the bottom of the common charging hopper gable-shaped in section and by driving the outer plates at different speeds, the said mixing action can be increased.

A construction embodying the invention is illustrated in the drawing, in which- Figure 1 is an end elevation partly in section, and Fig. 2 a side elevation partly in section. o

In the construction illustrated, the central plate consists of two symmetrically arranged separate plate-like members a, b. The charging hopper d has a width equal to the combined thickness of both members a, b, and has the form shown in Fig. 1, that is to say, it is limited at the top and on the sides by straight surfaces, While the bottom is of gable-section. For charging the balls, a funnel g is provided on the side of the hopper d (Fig. 2). The outer plates f, g are mounted on the ends of two co-axial shafts z', lc. The outer platesf, g as well as the members a, of the central plate are formed with concentric grinding grooves c, e Which are exactly opposite to one another.

The members of the central plate are cut 1n such a manner at their abutting edges that a dovetailed annular groove Z, m is Y formed. This groove is engaged by a correspondingly formed web n of the casing sections. t, 7' in such a manner that by tightening the screws p, the members a, b are tightly pressed against each other and are securely retained in the casing. By constructing the central plate in the above manner the advantage is obtained that each part or member is interchangeable, this being very important when the wear is not uniform. Furthermore, the two grooved sides of the central plate may be formed in one operation and With one tool, the grooved members which are normally back to back facing each other. This insures the uniform formation of the grooves.

What I claimas my invention and desire to secure by Letters Patent is:

1. In a ball grinding machine, the combination of a pair of rotatable plates arranged in spaced, parallel relation to each other and having their inner faces formed with annular grooves; and a stationary plate fitting in the space between the firstnamed plates and formed upon its opposite faces with annular grooves registering with the first-named grooves, said stationary plate being provided with a recess which has a Width equal to the thickness of that plate.

2.. In a ball-grinding machine, the combination of a pair of rotatable plates arranged in spaced, parallel relation to each other and having their inner faces formed with annular grooves; and .a stationary plate fitting in the space'between the first-named plates and formed upon its opposite faces with annular grooves registering with the first-named grooves, said stationary plate being provided Witha charging recess which has a width equal to the thickness thereof and which has a gable-shaped bottom.

3. In a ball-grinding machine, the combination of a pair of rotatable plates arranged in spaced, parallel relation to each other and having their'nner faces formed with annular grooves; alstationary plate fitting in the space between the `rst-named plates and consisting of a pair of juxtaposed, counterpart plate-like members formed at their abutting peripheral edges With a dove-tailed groove, said stationary plate being provided Awith a recess having a Width equal to the 'combined thickness of said members; and a Sectional casing encircling said plates and provlded With an annular Web for reception in said dove-tailed groove, to .force said mf 

